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Gut dysbiosis is common in patients with chronic kidney disease (CKD) and is associated with uremic toxin production, inflammation, oxidative stress, and cardiovascular disease development. Therefore, healthy dietary patterns are essential modulators of gut microbiota. In this context, studies suggest that consuming berry fruits, rich in polyphenols and nutrients, may positively affect the gut microbiota, promoting the selective growth of beneficial bacteria and improving clinical status. However, studies on the effects of berry fruits on gut microbiota in CKD are scarce, and a better understanding of the possible mechanisms of action of berry fruits on gut microbiota is needed to guide future clinical studies and clinical practice in CKD. The objective was to discuss how berry fruits (blueberry, cranberry, raspberry, and strawberry) could be a therapeutic strategy to modulate the gut microbiota and possibly reverse the dysbiosis in CKD. Overall, available evidence shows that berry fruits can promote an increase in diversity by affecting the abundance of mucus-producing bacteria and short-chain fatty acids. Moreover, these fruits can increase the expression of mRNA involved in tight junctions in the gut such as occludin, tight junction protein 1 (TJP1), and mucin. Studies on the exact amount of berries leading to these effects show heterogeneous findings. However, it is known that, with 5 mg/day, it is already possible to observe some effects in animal models. Wild berries could possibly improve the uremic condition by reducing the levels of uremic toxins via modulation of the gut microbiota. In the long term, this could be an excellent strategy for patients with CKD. Therefore, clinical studies are encouraged to evaluate better these effects on CKD as well as the safe amount of these fruits in order to promote a better quality of life or even the survival of these patients.

Chronic kidney disease (CKD) manifests with systemic inflammation, oxidative stress, and gut dysbiosis, resulting in metabolic disorders and elevated rates of cardiovascular disease–associated death. These all correlate with a high economic cost to healthcare systems. Growing evidence indicates that diet is an indispensable ally in the prevention and management of CKD and its complications. In this context, the root vegetable beetroot (Beta vulgaris rubra) deserves special attention because it is a source of several bioactive compounds, such as nitrate, betaine, and betalain, and has shown beneficial effects in CKD, including reduction of blood pressure, anti-inflammatory effects, and antioxidant actions by scavenging radical oxidative species, as observed in preclinical studies. Beetroot consumption as a possible therapeutic strategy to improve the clinical treatment of patients with CKD and future directions for clinical studies are addressed in this narrative review.

Sulforaphane (SFN) is a sulfur-containing isothiocyanate found in cruciferous vegetables (Brassicaceae) and a well-known activator of nuclear factor-erythroid 2-related factor 2 (Nrf2), considered a master regulator of cellular antioxidant responses. Patients with chronic diseases, such as diabetes, cardiovascular disease, cancer, and chronic kidney disease (CKD) present with high levels of oxidative stress and a massive inflammatory burden associated with diminished Nrf2 and elevated nuclear transcription factor-κB-κB expression. Because it is a common constituent of dietary vegetables, the salutogenic properties of sulforaphane, especially it’s antioxidative and anti-inflammatory properties, have been explored as a nutritional intervention in a range of diseases of ageing, though data on CKD remain scarce. In this brief review, the effects of SFN as a senotherapeutic agent are described and a rationale is provided for studies that aim to explore the potential benefits of SFN-rich foods in patients with CKD.

BACKGROUND AND AIMS Inflammation and oxidative stress are involved in the mortality of patients with chronic kidney disease (CKD) on peritoneal dialysis (PD). In this context, propolis may mitigate inflammation, reducing mRNA expression of nuclear factor-kB (NF-kB) and levels of inflammatory markers as tumor necrosis factor-α (TNF-α). Several studies have been performed in vitro and in animals showing that propolis (a resin made by bees) has excellent anti-inflammatory properties. Only one study evaluated the effects of propolis in patients with CKD (stages 3 and 4) and showed a reduction in proteinuria and urinary MCP-1, but there is no study in patients with CKD on peritoneal dialysis (PD). The present study aimed to evaluate the effects of propolis supplementation on inflammatory markers in patients with CKD on PD. METHODS This is a longitudinal, randomized, double-blind, placebo-controlled trial with 19 patients randomized into two groups: propolis (4 capsules of 500 mg/day containing concentrated and standardized dry EPP-AF® green propolis extract) or placebo (4 capsules of 500 mg/day of magnesium stearate, silicon dioxide and microcrystalline cellulose as placebo) for 2 months. The inflammatory cytokines plasma levels such as TNF-α and interleukin-6 (IL-6) were evaluated by ELISA, and quantitative real-time PCR analyses were performed to evaluate the mRNA expression of NF-kB in peripheral blood mononuclear cells (PBMCs). Plasma malondialdehyde (MDA) levels, a peroxidation lipid marker, was measured as thiobarbituric acid reactive substances (TBARS). Routine parameters, including C-reactive protein (CRP), were analyzed using commercial kits. RESULTS All patients concluded the study: 10 patients in the propolis group [57.2 ± 13.7 years, five men, 6 (6–36) months on DP] and 9 in the placebo group [56.6 ± 14.7 years, two men, 6 (6–57) months on DP]. The obtained data revealed that the intervention did not affect the mRNA expression of NF-κB. However, the plasma levels of TNF-α reduced significantly after propolis supplementation (Table 1 and Fig. 1). There were no significant differences in the placebo group. CONCLUSION Short-term EPP-AF® propolis dry extract supplementation seems to mitigate inflammation, reducing the plasma levels of TNF-α in patients with CKD on PD.

BACKGROUND AND AIMS Oxidative stress and inflammation are involved in the pathophysiological mechanisms in patients with chronic kidney disease (CKD) on hemodialysis (HD). In this context, the therapeutic potential of targeting the gene transcription factors associated with these mechanisms has been studied; for instance, nuclear factor erythroid 2-related factor 2 (Nrf2), the master regulator of antioxidant responses and, nuclear factor κappa B (NF-κB) that promotes the inflammatory response. However, the effects of physical exercise on the modulation of these factors are under investigation in CKD patients. Therefore, the aim of the present study was to evaluate the effects of an intradialytic aerobic exercise training program on the expression of transcription factors (Nrf2 and NF-κB) in patients with CKD on HD. METHODS This is a longitudinal, randomized clinical trial with a washout period and crossover performed with 18 patients randomized into two groups: Exercise (individualized intradialytic aerobic exercise on an adapted stationary exercise bike) three times per week for 3 months and control (without exercise). After the washout period (1 month), the exercise group became the control, and the other group performed the exercises for another 3 months. Peripheral blood mononuclear cells (PBMCs) were isolated, and quantitative real-time PCR analysis was performed to evaluate Nrf2, NF-kB and NAD(P)H: quinone oxidoreductase-1 (NQO1) mRNA expression. The plasma levels of inflammatory cytokines, tumour necrosis factor-α (TNF-α), C-reactive protein (CRP) and interleukin-6 (IL-6) were evaluated by ELISA. RESULTS Eighteen patients [11 men, 44.1 ± 8.4 years, 17.3 (6.6–124) months on HD] completed all the study. The obtained data revealed that the intervention did not affect the mRNA expression of Nrf2, NQO1 and NF-κB (Table 1). Also, TNF-α levels were not changed. However, IL-6 showed a tendency to decrease after the exercise intervention (P = 0.054). CONCLUSION Three months of intradialytic aerobic exercise were insufficient for modulating the transcription factors associated with antioxidant activity (Nrf2 and NQO1) and inflammation (NF-κB) in patients with CKD.

BACKGROUND AND AIMS Patients with chronic kidney disease (CKD), especially on hemodialysis (HD), have a high prevalence of cardiovascular mortality, with oxidative stress (OE) and inflammation as the main contributors. Persistent inflammation from the early stages of CKD is caused by several factors, including increased production of reactive oxygen species (ROS), leading to OE, which in turn induces inflammation by activating the nuclear factor-kB pathway, causing the overproduction of inflammatory cytokines such as tumour necrosis factor-alpha (TNF-α) and interleukins (IL). Dark chocolate is rich in polyphenols, which have antioxidant, anti-inflammatory and cardioprotective properties, and it could be an alternative nonpharmacological to mitigate inflammation and complications of CKD. Therefore, this study aimed to evaluate the effects of dark chocolate on oxidative stress and inflammation in patients with CKD on HD. METHODS This is a longitudinal clinical trial performed with 46 patients with CKD on a regular dialysis program (3 dialysis sessions per week). A group received 40 g of dark chocolate during HD sessions, totaling 120 g per week, for 2 months, and a group did not receive any intervention. Plasma levels of TNF-α and IL-6 were evaluated using the ELISA method. Thiobarbituric acid reactive substances were performed to evaluate lipid peroxidation as malondialdehyde (MDA). Routine parameters were also analyzed using commercial kits. Changes in parameters were evaluated between the pre- and post-treatment. RESULTS Thirty-five patients performed the chocolate group (18 men, 53.4 ± 12.9 years old and 43.2 ± 30 months on HD) and 11 patients (7 men, 46.7 ± 10.9 years old and 55.2 ± 18.7 months on HD) the control group. Although TNF-α plasma levels did not reduce significantly after chocolate, the levels were increased in the control group (Table 1 and Fig. 1). The potassium plasma levels were reduced (from 5.9 ± 0.8 to 5.5 ± 0.8 mg/dL, P CONCLUSION Two months of dark chocolate intervention seem to modulate the TNF-α plasma levels (inflammation marker) in patients with CKD on hemodialysis. It is important to emphasize that dark intervention in this study did not increase the phosphorus plasma levels in patients with CKD on HD.

BACKGROUND AND AIMS BTB and CNC homology 1 (Bach1) is a protein into the cells that antagonizes the actions of nuclear factor erythroid 2-related factor-2 (Nrf2), a master regulator of cytoprotective responses. Bach1 binds to genomic DNA and can inhibit the synthesis of antioxidant enzymes, increasing inflammation. Bach1 may be a therapeutic target to mitigate inflammation in patients with chronic kidney disease (CKD). However, no clinical study has been reported on Bach1 in patients with CKD. This study aimed to evaluate Bach1 mRNA expression in different treatments of CKD, including patients on conservative treatment (non-dialysis), hemodialysis (HD) and peritoneal dialysis (PD). METHODS Twenty patients on HD (54.3 ± 13.7 years old, nine men), fifteen on PD (51.4 ± 14.9 years old, eight men) and thirteen non-dialysis patients (61.0 ± 6.9 years old, seven men, estimated glomerular filtration rate of 39.2 ± 9.6 mL/min/1.73 m2) were enrolled in the study. The peripheral blood mononuclear cells were isolated and processed to evaluate the expression of nuclear factor-kB (NF-kB), Nrf2 and Bach1 by quantitative real-time polymerase chain reaction. Malondialdehyde (MDA), a lipid peroxidation marker, and C-reactive protein (CRP) plasma levels were also measured. RESULTS Bach1 mRNA expression was significantly higher in patients on hemodialysis (P CONCLUSION Patients with CKD on HD patients seem to have upregulation of Bach1 mRNA expression compared to patients on conservative and DP treatment. The associations among Nrf2 and Bach1 expressions in these patients deserve further investigation.

Background Even though handgrip strength (HGS) is considered a simple and reliable method to evaluate muscle function and, indirectly, the nutritional status in clinical settings, there is still no consensus concerning its use in patients with chronic kidney disease (CKD) undergoing dialysis. This study presents a systematic review of the literature on the use of HGS as a parameter for nutritional assessment and a prognostic marker in patients on dialysis. Methods The MEDLINE database (1966 to October 2009) was consulted for this systematic review by using the search terms hand strength or muscle strength dynamometer and dialysis. Eighteen articles were identified and included in the analysis. Results Similar to the general population, HGS values were associated with age and gender. The analysed studies showed correlation between muscle function estimated by HGS and variables used in the assessment of muscle mass and nutritional status, as well as the prediction of clinical complications. Conclusions The analysis indicates that HGS is a useful tool for continuous and systematic assessment of muscle mass related to nutritional status in patients on dialysis. However, it is still necessary to standardize the techniques used for HGS, especially with respect to the position of measurement, the evaluation period, the choice of arm side and the diagnostic criterion.